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Manipulated Optical Absorption and Accompanied Photocurrent Using Magnetic Field in Charger Transfer Engineered C/ZnO Nanowires

ABSTRACT: Abstract The rarely explored, spin?polarized band engineering, enables direct dynamic control of the magneto?optical absorption (MOA) and associated magneto?photocurrent (MPC) by a magnetic field, greatly enhancing the range of applicability of photosensitive semiconductor materials. It is demonstrated that large negative and positive MOA and MPC effects can be tuned alternately in amorphous carbon (a?C)/ZnO nanowires by controlling the sp2/sp3 ratio of a?C. A sizeable enhancement of the MPC ratio (?15%) appears at a relatively low magnetic field (?0.2 T). Simulated two peaks spin?polarized density of states is applied to explain that the alternate sign switching of the MOA is mainly related to the charge transfer between ZnO and C. The results indicate that the enhanced magnetic field performance of (a?C)/ZnO nanowires may have applications in renewable energy?related fields and tunable magneto?photonics. The alternate magnetic?field?manipulated optical absorption (MOA) and associated photocurrent can be engineered by spin?polarized band at room temperature. Simulated two peaks spin?polarized density of states is applied to explain that the alternate sign switching of the MOA is mainly related to the charge transfer between ZnO and C.

SUBMITTER: Lin J

PROVIDER: S-EPMC7533846 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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